Question

我有以下Bean：

package com.linknet.beans;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import javax.faces.bean.ManagedBean;
import javax.faces.bean.ViewScoped;
import javax.faces.model.SelectItem;
import javax.faces.model.SelectItemGroup;

import com.linknet.data.Device;
import com.linknet.data.DeviceFactory;

@ManagedBean(name = "deviceSwitcherBean")
@ViewScoped
public class DeviceSwitcherBean implements Serializable {

    public DeviceSwitcherBean() {

        this.now = new Date();
        System.out.println("PRINT DEVICES");
        this.devices = new DeviceFactory().createDevices("http://localhost:8080/DeviceCommander/resources/xml/DevliceList.xml");
        this.currentDevice = this.devices.get(0);

        //System.out.println(this.currentDevice.toString());

        SelectItemGroup g1 = new SelectItemGroup("Devices");
        ArrayList<SelectItem> items = new ArrayList<SelectItem>();
        for ( Device d : this.devices ) {
            items.add(new SelectItem(d,d.getName()));
        }
        System.out.println("PRINT 2");
        g1.setSelectItems(items.toArray(new SelectItem[0]));


        devs = new ArrayList<SelectItem>();
        devs.add(g1);

    }
    public void updateDate() {
        this.now = new Date();
        System.out.println("lel");
    }

    public void deviceSwitch() {
        System.out.println("Kayla");
        //System.out.println(getDevice());
    }


    public ArrayList<Device> getDevices() {
        return devices;
    }

    public void setDevices(ArrayList<Device> devices) {
        this.devices = devices;
    }

    public Device getCurrentDevice() {
        return currentDevice;
    }
    public void setCurrentDevice(Device currentDevice) {
        this.currentDevice = currentDevice;
    }

    public Date getNow() {
        return now;
    }

    public void setNow(Date now) {
        this.now = now;
    }
    //private String device;

    public List<SelectItem> getDevs() {
        return devs;
    }
    public void setDevs(List<SelectItem> devs) {
        this.devs = devs;
    }
    private List<SelectItem> devs;

    private ArrayList<Device> devices;
    private Device currentDevice;
    private Date now;
    private static final long serialVersionUID = 1L;
    //private ArrayList<String> devices;
}

我的xhtml是：

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
    xmlns:ui="http://java.sun.com/jsf/facelets"
    xmlns:h="http://java.sun.com/jsf/html"
    xmlns:f="http://java.sun.com/jsf/core"
    xmlns:c="http://java.sun.com/jsp/jstl/core"
    xmlns:fn="http://java.sun.com/jsp/jstl/functions"
    xmlns:p="http://primefaces.org/ui" xmlns:i="http://image">
<h:head>
    <link rel="shortcut icon"
        href="http://localhost:8080/DeviceCommander/resources/images/favicon.ico" />
    <title>DeviceCommander</title>
</h:head>
<h:body>
    <h:form id="page">

        <p:layout fullPage="true">
            <p:layoutUnit id="up" position="north" size="130" header="" resizable="true" closable="fals" collapsible="true">
                <h:panelGrid columns="4" cellpadding="5">
                    <p:row>
                        <p:column>
                            <h:graphicImage value="resources/images/tv.jpg" height="70" width="120" />
                        </p:column>
                        <p:column>
                            <h:form id="time">
                                <p:column>
                                    <h:outputText value="#{display.date}: " />  
                                    <h:outputText id="now" value="#{deviceSwitcherBean.now}" /> 

                                </p:column>
                            </h:form>
                        </p:column>
                        <p:column>
                            <h:outputText value="#{display.theme}: " />
                            <p:themeSwitcher effectSpeed="normal" effect="fade" style="width:165px" id="defaultSwitcher" value="#{themeSwitcherBean.theme}">
                                <f:selectItem itemLabel="#{display.select} #{display.theme}" itemValue="" />
                                <f:selectItems value="#{themeSwitcherBean.themes}" />
                                <p:ajax global="false" listener="#{themeSwitcherBean.saveTheme}" />
                            </p:themeSwitcher>
                        </p:column> 
                        <p:column>
                            <h:outputText value="#{display.device}: " for="deviceSelection"/>                           
                            <p:selectOneMenu id="deviceSelection" value="#{deviceSwitcherBean.currentDevice}" >
                                <f:selectItem itemLabel="Select One" itemValue="" />
                                <f:selectItems value="#{deviceSwitcherBean.devs}" />
                            </p:selectOneMenu>
                        </p:column>
                    </p:row>
                </h:panelGrid>  
            </p:layoutUnit>
        </p:layout>


        <p:layoutUnit position="center">
            <h:panelGrid id="main" columns="2" cellpadding="15">
                <p:row>
                    <p:dataTable var="deviceData" id="deviceData" value="1" >
                        <h:form id="device">
                        <p:column colspan="1" > 
                            <h:form id="remote"> 

                            </h:form> 
                        </p:column>
                        <p:column colspan="3" >
                            <h:form id="stream"> 

                            </h:form> 
                        </p:column>
                        <p:column colspan="1" >
                            <h:form id="view"> 

                            </h:form> 
                        </p:column>
                        </h:form> 
                    </p:dataTable>  
                </p:row>
            </h:panelGrid>
        </p:layoutUnit>


    </h:form>
</h:body>
</html>

问题是时间每秒更新一次但是从bean的构造函数更新时间，而updateDate（）根本没有被调用。为什么会这样？

Answer 1

解决BalusC文章中提到的问题。

Nesting form elements is invalid in HTML. Since JSF just generates a bunch of HTML, it's not different in JSF. Nesting h:form is therefore also invalid in JSF.

工作代码记录输出

PRINT DEVICES
PRINT 2
lel
lel
lel
lel

 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
    xmlns:ui="http://java.sun.com/jsf/facelets"
    xmlns:h="http://java.sun.com/jsf/html"
    xmlns:f="http://java.sun.com/jsf/core"
    xmlns:c="http://java.sun.com/jsp/jstl/core"
    xmlns:fn="http://java.sun.com/jsp/jstl/functions"
    xmlns:p="http://primefaces.org/ui" xmlns:i="http://image">
<h:head>
    <title>DeviceCommander</title>
</h:head>
<h:body>
    <h:form>
        <h:outputText value="#{display.date}: " />
        <h:outputText id="now" value="#{deviceSwitcherBean.now}" />
        <p:poll interval="1" listener="#{deviceSwitcherBean.updateDate()}"
            update="now" />
    </h:form>
</h:body>
</html>

Primefaces 6 - 民意调查

1 个答案: